Printing device for calculating machines

ABSTRACT

A printing device for a calculating machine comprises a set of toothed type wheels mutually distanced less that a set of reciprocable actuators connected thereto and apt to be rotated differentially. Also the pitch of the type wheels is less that the pitch of the reciprocable actuators. Each type wheel is rotated by the relevant actuator through a rack pivoted on the actuator and motion reducing gear meshing with the type wheel.

United States Patent Azzalin et al. 1 1 May 29, 1973 1 PRINTING DEVICE FOR 3,259,058 7/1966 Gassino etal. ..235/58 P CALCULATING MACHINES 3,610,518 10/1971 Metschnabl ..235/58 P [75] Inventors: Bruno Azzalin, l00l5 lvrea, Turin;

Domenico Bertina, 10010 Parella, Primary Examlfler stephen Tomsky Turin both of Italy Attorney-Kevin McMahon [73] Assignee: Ing. C. Olivetti & C., Ivrea 5 ABSTRACT (Turin), ltaly v A printing device for a calculating machine comprises [22] Flled: 1972 a set of toothed type wheels mutually distanced less 211 App]. 245,073 that a set of reciprocable actuators connected thereto and apt to be rotated differentially. Also the pitch of th h l'] 'thtth 'thfth 52 US. Cl. ..235/58 P, 235/60 P 211321? 8 ess a e e reclpmca [51] ..G06c 11/04 [58] Field of Search ..235/58 P, 60 P; Each type wheel is rotated by the relevant actuator 1 01/93 C, 79 through a rack pivoted on the actuator and motion reducing gear meshing with the type wheel. [56] References Cited UNITED STATES PATENTS 5 Claims, 2 Drawing Figures 2,340,261 1/1944 Eichler ..235/60 P BACKGROUND OF THE INVENTION l. Field of the Invention This invention relates to a printing device for calculating machines, comprising a set of reciprocable actuators differentially movable to represent an amount and a set of type wheels each one fulcrumed on a corresponding member movable toward the paper platen to enable said wheels to print said amount, said type wheels being provided with teeth and carrying the types on the external surface thereof, said type wheels being spaced according to a printing space substantially smaller than the mutual transverse distance of said actuators and being each positioned by a rack fulcrumed on the corresponding actuator, the pitch of said type wheels being substantially greater than the pitch of said actuators.

2. Description of the Prior Art The actuators of mechanical calculating machines are generally so distanced as to take into account the transverse dimensions of the totalizer and of the other devices of the machinewsuch a distance is relatively large, whereby the figures are printed on the paper with an excessive letter space, which is unpleasant to the reader. In addition, the modern automatic character recognition techniques, for example the optical character recognition, require aprint work having a letter space smaller than the mutual transverse distance of the actuators.

Several printers for calculating machines for printing according to a space smaller than the mutual distance of the actuators have been already suggested, for example by connecting the type carriers to the corresponding actuators by means of arms suitably bent so as to converge toward the center. These devices are unadapted for calculating machines, having type wheels carried by members which are movable toward the platen and constantly connected to the actuators.

' Other known printing devices are provided with toothed type wheels carrying the types on the external surface thereof, so as to reduce the mutual distance of the type wheels. Since generally the pitch of the actuators is relatively small, the types of these type wheels nately connecting each type wheel to the one or to the other of a pair of adjacent actuators. This device has the disadvantage that the type wheels must be laterally displaced and that the printing operation is always carried out in two subsequent machine cycles.

SUMMARY OF THE INVENTION These disadvantages are obviated by the printing de vice according to the invention, which is characterized in that each one of said type wheels constantly engages a corresponding toothed wheel integral to a pinion, which is always in mesh with the toothed rack, said toothed wheel and said pinion being fulcrumed on the same movable member of the corresponding type wheel.

A preferred embodiment of the invention is disclosed, by way of example but not in a limiting sense,

by the following description and 'bythe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a printing device for calculating machines according to the invention;

FIG. 2 is a partial plan view of the device of the FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to the FIG. 1, the printing device comprises a set of type wheels 5 having types 6. The type wheels 5 are mutually transversely spaced a onetenth inch, which is the space required for optical character recognition. Each type wheel 5 is rotatable on a pin 7 secured to a horizontal slide 8. The type wheels 5 are toothed, the types 6 being located on the external surface of the teeth. Each type wheel 5 is directly in mesh with a gear 9 rotatable on another pin 11 of the slide 8. Each gear 9 is integral with a pinion 12 having a diameter shorter than that of the gear 9. The total thickness of the gear 9 and pinion 12 is substantially equal to that of the type wheel 5.

Each pinion 12 is in mesh with a rack 13 fulcrumed at 14 on an arm 15 carried by a conventional reciprocable actuator 16. The actuators 16 are differentially vertically movable under the control of a universal bar 17, for representing each time an amount, in a manner known per se. Each rack 13 is vertically guided between the slide 8 and the gear 9 by a comb 19, and is held constantly in mesh with the pinion 12 by a pin 18 secured to the slide 8. The actuators 16 are transversely mutually spaced approximately one-sixth inch, while the arms 15 are suitably horizontally bent for holding each one the corresponding rack 13 on a vertical plane which is adjacent to that of the corresponding slide 8, as shown in FIG. 2.

The slides 8 are movable for causing the types 6 to engage a conventional paper platen 20 (FIG. 1 Particularly, the slides 8 are horizontally slidable by means of two slots 21 and 22 on two shafts 23, and 24 respectively, which are secured to a pair of stationary plates 26 and 27 (FIG. 2) of the machine. The slides 8 are held at rest by a square universal bar 28 by the urge of corresponding springs 29 (FIG. 1) and are laterally guided by guiding combs 31, 32 and 33.

Fulcrumed at 35 on each slide 8 is a locking member 34, which is provided with a tooth 36 adapted to be inserted between the types 6 of the corresponding type wheel 5. Each locking member 34 is also provided with a projection 37 normally contacting the lower face of the universal bar 28 by the urge of a spring 38. The locking members 34 have a thickness which is slightly less than the thickness of the type wheels 5, and are provided with an depression 39 (FIG. 2) adapted to allow the passage of the relevant rack 13 when this latter is raised for positioning the type wheel 5.

The two end portions of the universal bar 28 are secured to a pair of slides 40, 41 (FIG. 2) which are slidable on two extensions of the shaft 24 and on a pair of pins 44 secured to the plates 26 and 27, each one by means of a pair of slots 42 and 43 (FIG. 1). The slots 42 and 43 are shaped with a horizontal portion and a downward inclined portion. Each slide 40, 41 is connected to a lever 48, and 49 respectively, by means of a link 46, and 47 respectively. The levers 48 and 49 are secured to a shaft 51 rotatable on the plates 26 and 27 (FIG. 2) of the machine. The lever 48 is provided with an arm 52 (FIG. 1) connected by means of a link 53 to a forked lever 54 fulcrumed on a stationary pivot 56. The lever 54 cooperates by means of a pair of rollers 57 and 58 with a pair of complementary cams 59, 60 of a shaft 61, which represents the conventional main shaft of the machine and is cyclically rotatable counterclockwise.

Each slide 8 is also provided with a slot 62 entered by a fixed bar 63 cooperating with a projection 64 of the corresponding locking member 34, the slides 8 are controlled by known means adapted to selectively prevent them from printing, for example for excluding the non-significant zeros of an amount. Furthermore, means known per se and not shown in the drawing are provided for locking the slides 8 during the non-print" cycles. Finally, each slide 8 is provided with a projection 66 which is adapted to cooperate with a leaf spring 67 near the end of its travel.

The printing device operates as follows.

The actuators 16 are differentially displaced upwards in a known way for representing an amount, for example to be accumulated into the totalizer or a total to be taken from the same.

Each actuator 16 when displaced upwards causes the relevant rack 13 to rotate the relevant pinion 12 counterclockwise together with the gear 9. This latter rotates the type wheel clockwise, thus selecting the type 6 for printing. The cams 59 and 60 of the main shaft 61 cause the forked lever 54 to rock counterclockwise, thus raising the link 53. This latter rocks the arm 52, together with the shaft 51 and the levers 48 and 49, counterclockwise, thus pushing the links 46 and 47 rearwards (leftwards in FIG. 1). The slides 40, 41, being guided by the relevant slots 42, 43, cause the universal bar 28 to accomplish firstly a horizontal displacement and subsequently an inclined displacement to bring the bar 28 into the position shown by dot-anddash lines in FIG. 1. The springs 29 pull the relevant slides 8 backwards, thus displacing the type wheels 5 toward the platen 20.

Since the projections 37 of the locking members 34 are not stopped by the universal bar 28, the members 34 are rocked counterclockwise by the springs 38 until inserting the teeth 36 into one of the vanes between the types 6 of the type wheel 5. The locking members 34 corresponding to the slides 8, which are not displaced toward the platen during the printing cycles, bear their projections 64 against the stationary bar 63, thus preventing a useless wear of the teeth 36. Similiarly, in the non-printing cycles, during which the slides 8 are not displaced toward the platen 20, the locking members 34 are stopped by the stationary bar 63, thus allowing the upward movement of the actuators 16.

Just before the type wheels 5 contact the platen 20, the projections 66 of the slides 8 engage the leaf spring 67, whereby the types 6 engage the platen 20, while the wheels 5 are locked by the locking members 34 and the springs 67 are bent by the projections 66, as shown by dot-and-dash lines in FIG. 1. Thereafter the springs 67 quickly reset the slides 8 forewards, thus preventing the rebound against the platen 20, due to the spring 29.

After the main shaft 61 has rotated 180 degrees, the cams 59 and 60 rock the forked lever 54 clockwise, thus resetting the slides 40 and 41 to the rest position. The universal bar 28 is lowered and pushes the projections 37 downwards, thus rocking the locking members 34 clockwise against the urge of the springs 38. Therefore, the locking members 34 begin to disengage the type wheels 5 before resetting the slides 8. The actuators 16 are reset by the bar 17 in a known manner and zeroize the type wheels 5 by rotating them counterclockwise by means of the racks 13 the pinions l2 and the gears 9. The universal bar 28 is then restored against the urge of the springs 29, thus resetting the slides 8.

It becomes therefore apparent that each type wheel 5 is constantly in mesh with the corresponding gear 9 integral to the pinion 12, which is constantly in mesh with the relevant rack 13, and that the gear 9 and the pinion 12 are fulcrumed on the same slide 8 fulcruming the type wheel 5.

It is intended that many changes, improvements and additions of parts may be made to the printing device without departing from the scope of the invention.

What we claim is:

l. A printing device for calculating machines, comprising a paper platen, a set of reciprocable actuators differentially moveable to represent an amount, a set of toothed type wheels carrying the types on the external surface thereof and being spaced according to a printing space substantially smaller than the mutual transverse distance of said actuators, a set of movable members each one pivotally mounting a corresponding one of said type wheels and movable toward said platen to enable said type wheels to print said amount, and a set of racks each one fulcrumed on the corresponding one of said actuators, the pitch of said type wheels being substantially greater than the pitch of said actuators, wherein the improvement comprises:

a gear fulcrumed on each one of said movable members and constantly in mesh with the corresponding type wheel,

and a pinion having a diameter smaller than that of said gear and coaxially secured thereto, said pinion constantly meshing with said rack, whereby the motion of each one of said racks in amplifiedly transmitted to the corresponding type wheel.

2. A printing device according to claim 1, wherein each one of said racks is held in mesh with saidpinion by a guide carried by the corresponding movable member, each one of said racks being fulcrumed on an arm integral to the corresponding actuator, said arms being so shaped as to hold the corresponding racks mutually I spaced according to said printing space.

3. A printing device according to claim 1, comprising an universal bar for controlling said movable members, and a locking member carried by each of said movable members and actuatable by said universal bar for being engaged between the teeth of the corresponding type wheel during at least a portion of its displacement toward said platen.

4. A printing device according to claim 3, wherein each of said movable members is a slide slidable on a horizontal path, and wherein said universal bar is cyclically moved under the control of a main shaft through a first displacement parallely to said slides for allowing said type wheels to print and through a second displacement inclined with respect to said path for allowing said locking members to engage the relevant type wheels.

5. A printing device according to claim 1, wherein each one of said movable members comprises a projection for engaging a stationary resilient element, before said type wheels contact said platen. 

1. A printing device for calculating machines, comprising a paper platen, a set of reciprocable actuators differentially moveable to represent an amount, a set of toothed type wheels carrying the types on the external surface thereof and being spaced according to a printing space substantially smaller than the mutual transverse distance of said actuators, a set of movable members each one pivotally mounting a corresponding one of said type wheels and movable toward said platen to enable said type wheels to print said amount, and a set of racks each one fulcrumed on the corresponding one of said actuators, the pitch of said type wheels being substantially greater than the pitch of said actuators, wherein the improvement comprises: a gear fulcrumed on each one of said movable members and constantly in mesh with the corresponding type wheel, and a pinion having a diameter smaller than that of said gear and coaxially secured thereto, said pinion constantly meshing with said rack, whereby the motion of each one of said racks in amplifiedly transmitted to the corresponding type wheel.
 2. A printing device according to claim 1, wherein each one of said racks is held in mesh with said pinion by a guide carried by the corresponding movable member, each one of said racks being fulcrumed on an arm integral to the corresponding actuator, said arms being so shaped as to hold the corresponding racks mutually spaced according to said printing space.
 3. A printing device according to claim 1, comprising an universal bar for controlling said movable members, and a locking member carried by each of said movable members and actuatable by said universal bar for being engaged between the teeth of the corresponding type wheel during at least a portion of its displacement toward said platen.
 4. A printing device according to claim 3, wherein each of said movable members is a slide slidable on a horizontal path, and wherein said universal bar is cyclically moved under the control of a main shaft through a first displacement parallely to said slides for allowing said type wheels to print and through a second displacement inclined with respect to said path for allowing said locking members to engage the relevant type wheels.
 5. A printing device according to claim 1, wherein each one of said movable members comprises a projection for engaging a stationary resilient element, before said type wheels contact said platen. 